1. Field of the Invention
The present invention relates to safety locks for doors. More specifically, the present invention relates to a disturbance responsive magnetic latch for mounting on cabinet doors which is responsive to vibrations, shaking, and other disturbances such as those encountered in seismic events, moving vehicles, boats, and the like.
2. Description of Prior Art
Numerous latching devices have been proposed and implemented for securing cabinets, windows, and doors in a closed position. Such latching devices are set to be in either a locked or an unlocked position. As such, these devices do not provide for protection against sudden vibrations or movement caused by earthquakes or other seismic events, for example, when conventional latches are often dislodged from their locked position and the contents scattered and in many cases destroyed. Abrupt and sudden disturbances are also often encountered in vehicles such as airplanes, automobiles, motor homes, boats, and the like. In such situations conventional approaches to latching doors is often inadequate to protect against such disturbances often with disastrous results. Furthermore, such latches, since they are either in an on or locked position at all times are not useful as a backup safety latches. Two such devices may not be used in combination with each other in order to provide a backup or safety feature because either both will be in the locked position and thus interfering with normal usage of the doors, or if one is locked and the other left unlocked there is no backup or safety function achieved, and if both are left unlocked there is no protection whatever and in fact the doors will remain open.
A search of the prior art did not disclose any patents that read directly on the claim of the instant invention, however, the following U.S. Patents were considered related;
U.S. Pat. No. 4,848,812 issued to Slaughter, July 18, 1989
U.S. Pat. No. 4,452,475 issued to Bloch et al, June 5, 1984
U.S. Pat. No. 3,844,597 issued to Elrod et al., Oct. 29, 1974
U.S. Pat. No. 3,635,511 issued to Waller, Jan. 18, 1972
U.S. Pat. No. 3,388,938 issued to Peterson, June 18, 1968
U.S. Pat. No. 3,312,492 issued to Remhof, Apr. 4, 1967
U.S. Pat. No. 2,971,789 issued to Weaver, Feb. 14, 1961.
Slaughter discloses a concealed safety lock having a magnetic bolt disposed within a throughbore of the device. This device was used in either an on or locked position or an open or unlocked position. No means were provided which could activate the locking mechanism by sudden motion or other disturbances and thus such device was severely limited in use and application as either a backup safety latch or as a latch responsive to sudden vibrations or other disturbances.
Bolch et al. show a door with a magnetic sealing strip as a latching device. Such device prevented the opening or unlatching of the door due to sudden motion, however, it was not activated by such motion and as such was, when activated, always in a locked position.
The Waller, Remhof, and Weaver patents all disclose latching devices of a genre where magnets are used to lock a latch in a closed position. None show a device which is activated or locked by sudden movements. Nor are any of these patents useful as a backup or as a safety latch
The remaining prior art disclose mechanical devices to latch doors or lids shut and are included for illustration and are representative of the art to which this invention relates.
It would be very desirable therefore to have a disturbance responsive latch which is activated by vertical or horizontal motion such as that encounter in earthquakes, moving vehicles, boats, and the like. It would also be desirable to have such latch which could be used in combination with conventional latches without interfering with their function or the normal opening and closing of the door.
It is therefore an object of the present invention to provide a disturbance responsive latch mechanism which is responsive to vertical and horizontal shaking or rocking motions for securing cupboard doors and the like.